1. Field of the Invention
The present invention relates to a wheel rim, and more particularly to a wheel rim for bicycles.
2. Description of the Prior Art
Typical wheel rims for bicycles comprise two sides of smooth outer surfaces for engaging with the brake pads. When riding in the raining days, the smooth outer surfaces may become slip such that the brake pads may not be used for effectively engaging with the wheel rim and for braking the bicycles.
The present invention has arisen to mitigate and/or obviate the afore-described disadvantages of the conventional wheel rims for bicycles.